The present invention relates to an apparatus for counting small objects, such as screws, and for filling the objects into bags. Apparatus of this type is known which has a circular pot-shaped vibratory conveyor which conveys the object piece-by-piece to a transporting device which operates at a high speed to further separate the transported object. It is also known to provide a photoelectric sensor which cooperates with an electric control and counting device which counts up to a predetermined number of pulses produced by the photocell, and thereby counts the number of objects. The vibratory conveyor and the transporting means are controlled by the control and counting device.
In a known apparatus of this type, a tangential outlet channel is connected with the vibratory conveyor, through which small objects are piled up on a transporting band. Since the objects can move in the outlet channel or chute only at a limited speed, the output is comparatively low. The small objects can freely move on a transporting band and approach each other, so that the desired separation of the objects for the purpose of reliably counting the objects, cannot be obtained. At great transporting speed, there is the possibility that the separation by gravity is insufficient.
It is one object of the invention to provide an apparatus which transports small objects at a high speed, while reliably separating the transported objects.
Another object of the invention is to provide an apparatus capable of supplying different counted objects to a receptacle.
With these objects in view, the present invention provides that the output of a pot-shaped vibratory conveyor is at least substantially located on the circular path of the pot-shaped conveyor, and is directly followed by transporting means operating in tangential direction. A container, which can be closed and opened for discharge, follows the transporting means, and receives the transported objects successively. Due to the direct connection of a transporting means with the vibratory conveyor, the maximum speed can be utilized at which the vibratory container can supply the separated objects.
The collection, first in a container, permits the combination of several units, each of which includes a vibratory conveyor, a transporting means, a container for the transported objects, and a chute, so that the outlets of the chutes can be combined, permitting assorted different small objects to be placed in counted numbers. in a bag at a filling station.
The closures for the containers, which are preferably electro-mechanically operated, can be controlled by a control device, and permit discharge from the containers into the chutes only when all containers have collected the respective selected number of objects.
The operation can be fully automatically carried out, if the units are part of a filling arrangement in which bags or the like are automatically supplied to a filling station, filled with the objects for the apparatus of the invention, and then removed in filled condition.
In order to assure that small objects are singly transported to the outlet of the vibratory conveyor, and to the inlet of the transporting means, the spiral guide ramp of the pot-shaped vibratory conveyor tapers toward the outlet, and a track is provided thereon which may be a slot in which screws can be suspended with the heads sliding on parallel track portions forming a slot for the screws.
In one embodiment of the invention, the transporting means include two endless belts having confronting parallel belt portions forming between each other a gap of constant width. The confronting belt portion hold the objects immovably while transporting the same toward the outlet so that the objects cannot be displaced while being transported by the endless belts.
If the small objects are conical, for example wood screws, there is the danger that the conical objects are pushed out in vertical upward direction from the slot between the endless belts, so that the objects would not pass a photoelectric sensor in this region, and consequently would not be counted. In order to avoid such disadvantage, the invention provides above the gap formed by the confronting belt portions, a guide means on which the tops of the objects slide while being transported, so that the objects are retained in the slot, and are reliably counted.
It is an important feature of the invention that a photoelectric sensing means is arranged in the region of the transporting means, preferably underneath the endless belts. The light beam of the photoelectric sensor is interrupted by each object while the same is transported by the confronting belt portions. Due to the firm hold of the objects by the transporting belts, the separation of successive objects is reliably achieved, and the speed at which the objects are transported through the light beam, can be substantially higher than the speed obtained by free fall, as in the prior art.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.